If certain malfunctions occur in laundry machines, such as tumbler dryers, which are not promptly detected, excessive damage can occur to the machine and potentially dangerous conditions can arise. Tumbler dryers typically have a belt-driven rotary tumbler basket within which laundered items are tumbled during drying. The tumbler basket is perforated and heated air is directed into the basket from an air inlet to the basket as the items are tumbled and discharged from an outlet side of the basket.
Problems in the operation of tumbler dryers often arise by reason of items left in the pockets of clothes or other garments being laundered. Nails, screws, and other elongated metal items inadvertently left in the pockets of items during laundering can work their way free of the garments during tumbling and migrate to the outer wall of the tumbler basket by reason of centrifugal forces. Such nails and screws quickly find their way through the perforations in the basket with the heads of the fasteners, which are larger than the basket openings, retaining the fasteners in outwardly protruding relation to the basket such that continued rotation of the basket causes the metal fasteners to gauge and damage sheet metal interior panels of the dryer. Fasteners, such as drywall nails, are particularly troublesome since ridges on the shank of the nail tend to prevent dislodgement of the nail from the perforation of the basket even when gauging the interior dryer panels. Such obstructing nails and screws can quickly tear openings into the interior of the dryer which permit ambient air to enter the tumbler from the openings, rather than from the heated air inlet, which in turn can lead to overheating at the inlet of the dryer and the potential for fire.
Potentially hazardous fire conditions also can rapidly arise by reason of a broken or dislodged drive belt for the rotary basket of tumbler dryers. When rotation of the basket is stopped by reason of a break or uncoupling of the drive belt, the high temperature air introduced from the dryer inlet is concentrated on the item or items closest to the air inlet which are no longer being tumbled. Since the dryer often is unattended, a broken or dislodged drive belt can go undetected for some time resulting in overheating and potential ignition of the garments within the dryer.